diff --git a/src/Phaseolies/Database/Entity/Builder.php b/src/Phaseolies/Database/Entity/Builder.php
index 1b80e7a5..61438cfb 100644
--- a/src/Phaseolies/Database/Entity/Builder.php
+++ b/src/Phaseolies/Database/Entity/Builder.php
@@ -225,7 +225,7 @@ public function select(array|string ...$fields): self
      */
     public function where($field, $operator = null, $value = null): self
     {
-        if (is_callable($field)) {
+        if ($this->isCallback($field)) {
             return $this->whereNested($field, 'AND');
         }
 
@@ -259,7 +259,7 @@ public function where($field, $operator = null, $value = null): self
      */
     public function orWhere($field, $operator = null, $value = null): self
     {
-        if (is_callable($field)) {
+        if ($this->isCallback($field)) {
             return $this->whereNested($field, 'OR');
         }
 
@@ -744,7 +744,7 @@ private function escapeValue($value): string
      */
     public function if($value, callable $callback, ?callable $default = null): self
     {
-        $payload = is_callable($value) ? $value() : $value;
+        $payload = $this->isCallback($value) ? $value() : $value;
 
         if ($payload === true || $this->hasValue($payload)) {
             $callback($this);
@@ -1363,7 +1363,7 @@ public function load($relations, ?callable $callback = null): self
 
         foreach ($relations as $key => $value) {
             $relation = is_string($key) ? $key : $value;
-            $constraint = is_callable($value) ? $value : $callback;
+            $constraint = $this->isCallback($value) ? $value : $callback;
 
             if (str_contains($relation, '.')) {
                 $this->loadNestedRelations($models, $relation, $constraint);
@@ -1654,7 +1654,7 @@ public function embedCount($relations, ?callable $callback = null): self
 
         if (is_array($relations)) {
             foreach ($relations as $key => $value) {
-                if (is_callable($value)) {
+                if ($this->isCallback($value)) {
                     $this->eagerLoad["count:{$key}"] = $value;
                 } else {
                     $this->eagerLoad["count:{$value}"] = null;
@@ -1953,7 +1953,7 @@ public function embed($relations, ?callable $callback = null): self
 
         if (is_array($relations)) {
             foreach ($relations as $key => $value) {
-                if (is_callable($value)) {
+                if ($this->isCallback($value)) {
                     // Format: ['comments' => function($q) { ... }]
                     [$relationName, $columns] = $this->parseRelationWithColumns($key);
                     $constraint = !empty($columns)
diff --git a/src/Phaseolies/Database/Entity/Query/Builder.php b/src/Phaseolies/Database/Entity/Query/Builder.php
index 0aa3f974..3dcd1449 100644
--- a/src/Phaseolies/Database/Entity/Query/Builder.php
+++ b/src/Phaseolies/Database/Entity/Query/Builder.php
@@ -123,7 +123,7 @@ public function select(array|string ...$fields): self
      */
     public function where($field, $operator = null, $value = null): self
     {
-        if (is_callable($field)) {
+        if ($this->isCallback($field)) {
             return $this->whereNested($field, 'AND');
         }
 
@@ -157,7 +157,7 @@ public function where($field, $operator = null, $value = null): self
      */
     public function orWhere($field, $operator = null, $value = null): self
     {
-        if (is_callable($field)) {
+        if ($this->isCallback($field)) {
             return $this->whereNested($field, 'OR');
         }
 
@@ -359,7 +359,7 @@ protected function getTableColumns(?string $table = null): array
      */
     public function if($value, callable $callback, ?callable $default = null): self
     {
-        $payload = is_callable($value) ? $value() : $value;
+        $payload = $this->isCallback($value) ? $value() : $value;
 
         if ($payload === true || $this->hasValue($payload)) {
             $callback($this);
diff --git a/src/Phaseolies/Database/Entity/Query/Grammar.php b/src/Phaseolies/Database/Entity/Query/Grammar.php
index 457ad465..ff7464f5 100644
--- a/src/Phaseolies/Database/Entity/Query/Grammar.php
+++ b/src/Phaseolies/Database/Entity/Query/Grammar.php
@@ -28,6 +28,20 @@ protected function assertValidIdentifier(string $identifier): void
         }
     }
 
+    /**
+     * Determine if a value is a callback (closure, invokable or array callable).
+     *
+     * Strings are never treated as callbacks: names like "date" or "time"
+     * pass is_callable() but are column names or values here.
+     *
+     * @param mixed $value
+     * @return bool
+     */
+    protected function isCallback(mixed $value): bool
+    {
+        return !is_string($value) && is_callable($value);
+    }
+
     /**
      * Get the current driver
      *
diff --git a/tests/Builder/StringArgumentNotCallableTest.php b/tests/Builder/StringArgumentNotCallableTest.php
new file mode 100644
index 00000000..4846a736
--- /dev/null
+++ b/tests/Builder/StringArgumentNotCallableTest.php
@@ -0,0 +1,115 @@
+<?php
+
+namespace Tests\Unit\Builder;
+
+use PDO;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\DataProvider;
+use PHPUnit\Framework\Attributes\AllowMockObjectsWithoutExpectations;
+use Phaseolies\Database\Entity\Builder;
+use Phaseolies\Database\Entity\Query\Builder as QueryBuilder;
+
+/**
+ * Strings such as "date" or "time" pass is_callable() because they are PHP
+ * function names. The builders must treat them as column names / values,
+ * never invoke them as closures.
+ */
+#[AllowMockObjectsWithoutExpectations]
+class StringArgumentNotCallableTest extends TestCase
+{
+    private function entityBuilder(): Builder
+    {
+        $pdo = $this->createMock(PDO::class);
+        $pdo->method('getAttribute')->willReturn('mysql');
+
+        return new Builder($pdo, 'users', StringArgumentModelStub::class, 15);
+    }
+
+    private function queryBuilder(): QueryBuilder
+    {
+        $pdo = $this->createMock(PDO::class);
+        $pdo->method('getAttribute')->willReturn('mysql');
+
+        return new QueryBuilder($pdo, 'users');
+    }
+
+    public static function functionNamedColumns(): array
+    {
+        return [['date'], ['time'], ['key'], ['max'], ['min'], ['file'], ['end'], ['range']];
+    }
+
+    #[DataProvider('functionNamedColumns')]
+    public function testWhereOnColumnNamedLikePhpFunctionIsACondition(string $column): void
+    {
+        $sql = $this->entityBuilder()->where($column, 'x')->orWhere($column, '!=', 'y')->toSql();
+
+        $this->assertStringContainsString("{$column} = ?", $sql);
+        $this->assertStringContainsString("OR {$column} != ?", $sql);
+    }
+
+    #[DataProvider('functionNamedColumns')]
+    public function testQueryBuilderWhereOnColumnNamedLikePhpFunctionIsACondition(string $column): void
+    {
+        $sql = $this->queryBuilder()->where($column, 'x')->orWhere($column, 'y')->toSql();
+
+        $this->assertStringContainsString("{$column} = ?", $sql);
+        $this->assertStringContainsString("OR {$column} = ?", $sql);
+    }
+
+    public function testWhereStillAcceptsClosuresForNesting(): void
+    {
+        $sql = $this->entityBuilder()
+            ->where(fn($q) => $q->where('a', 1)->orWhere('b', 2))
+            ->toSql();
+
+        $this->assertStringContainsString('(a = ? OR b = ?)', $sql);
+    }
+
+    public function testWhereStillAcceptsInvokableObjectsForNesting(): void
+    {
+        $nested = new class {
+            public function __invoke($q): void
+            {
+                $q->where('a', 1);
+            }
+        };
+
+        $this->assertStringContainsString('(a = ?)', $this->queryBuilder()->where($nested)->toSql());
+    }
+
+    public function testIfDoesNotInvokeStringValuesAsFunctions(): void
+    {
+        $called = 0;
+        $callback = function () use (&$called) {
+            $called++;
+        };
+
+        // "phpinfo" would print the server configuration if invoked.
+        ob_start();
+        $this->entityBuilder()->if('phpinfo', $callback);
+        $this->queryBuilder()->if('phpinfo', $callback);
+        $output = ob_get_clean();
+
+        $this->assertSame('', $output);
+        $this->assertSame(2, $called);
+    }
+
+    public function testIfStillEvaluatesClosureConditions(): void
+    {
+        $called = false;
+
+        $this->entityBuilder()->if(fn() => false, function () use (&$called) {
+            $called = true;
+        });
+
+        $this->assertFalse($called);
+    }
+}
+
+class StringArgumentModelStub
+{
+    public function usesTimestamps(): bool
+    {
+        return false;
+    }
+}